Rev Limit
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Though there is no electronic rev limiter, the stock intake will limit the effective revs to low 5k range. Beyond that the stock valve train will likely limit you to below 6k RPM (only around 80lbs on the seat) and the bottom end will limit you to maybe low to mid 6k RPMs.
Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
I agree.
With the stock intake the engine will turn more than 5500, but the
party is over at 4400 and acceleration falls off noticably. My vote is
that the only reason to wind higher than 5000 is to avoid a gear
change.
With a stroke of 3.48, piston speed at 6000 is just under 3500 FPM.
This getting to the boundary of what the OEM bottom end components
are able to tolerate.
.
With the stock intake the engine will turn more than 5500, but the
party is over at 4400 and acceleration falls off noticably. My vote is
that the only reason to wind higher than 5000 is to avoid a gear
change.
With a stroke of 3.48, piston speed at 6000 is just under 3500 FPM.
This getting to the boundary of what the OEM bottom end components
are able to tolerate.
.
Racer
Joined: Nov 2004
Posts: 445
Likes: 0
5,600rpm on an 86...and I believe 86 and 88's have the same 165 ecm's...? Though the info in the chips would vary some...
Quote from 86 owner's manual.."When engine speed exceeds 5600rpm, the fuel injectors cease to function."
Quote from 86 owner's manual.."When engine speed exceeds 5600rpm, the fuel injectors cease to function."
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,257
Likes: 4
From: North Carolina
Thanks,
Dan
Melting Slicks
Joined: Aug 2003
Posts: 3,409
Likes: 400
From: Lakeville MI
The ecm's fuel cut rev limit is set to 10,031 rpm for L98s. Fuel resume is set to 9544 rpm.
With these settings the rev limit function has been effectively disabled from the factory.
For shift points: I would suggest as a starting point something like 4800 rpm 1-2, 4600 rpm 2-3 and 4400 rpm 3-4.
With these settings the rev limit function has been effectively disabled from the factory.
For shift points: I would suggest as a starting point something like 4800 rpm 1-2, 4600 rpm 2-3 and 4400 rpm 3-4.
Last edited by tequilaboy; Feb 27, 2007 at 03:38 PM.
Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
That self-imposed RPM peak will make for good engine longevity.
Shift earlier to go faster.
If you keep an eye out for signs of leaking head gaskets, use a
50:50ish mixture of glycol & distilled water as the coolant
and change it every two years, then you should receive hundreds
of thousands of miles of enjoyment from the engine.
The Lisle 75500 COMBUSTION LEAK DETECTOR (less than $30) and/or
regular oil analysis reports will provide early warning of impending
HG failure. If you see white exhaust or the dreaded chocolate
milkshake - it is probably too late for the bottom end.
See flannel_man's thread (un)Funny oil
.
.
Shift earlier to go faster.
If you keep an eye out for signs of leaking head gaskets, use a
50:50ish mixture of glycol & distilled water as the coolant
and change it every two years, then you should receive hundreds
of thousands of miles of enjoyment from the engine.
The Lisle 75500 COMBUSTION LEAK DETECTOR (less than $30) and/or
regular oil analysis reports will provide early warning of impending
HG failure. If you see white exhaust or the dreaded chocolate
milkshake - it is probably too late for the bottom end.
See flannel_man's thread (un)Funny oil
.
.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,257
Likes: 4
From: North Carolina
The honest reason I asked was because I launched the car yesterday just to get an idea of what it would do on the track (I know its different but I haven't really hammered this car at all yet) and although i like the digital dash its hard to tell what RPM the cars at... so I went by ear, and needless to say when I looked down the rpm was up around 5000- maybe 5300 if I happened to look down during my shift. In any event, I couldn't tell if it went into the red zone, but it was over the hump on the RPM gauge. Last thing I want to do is blow then engine on this thing, it runs great and gets 27.5MPG (better then a rice box might i add). I know the bottom can take about 7K if I had an accident so I am not too worried. My girlfriend is the primary driver and she baby's it all week. Meanwhile the previous owner raced it (we found slips for raceway park under the seat) so I really don't think any harm was caused during my 1 time overrev.... I think for the street 4K will do, and for the track I may let her go to 4500.
Thanks guys,
P.S. can I have it tuned with a Rev Limit like 5500?
Oh, also, changed the Synthetic oil at just around 3500 Miles, and it was down 1/4 of a quart... thats about what you guys are seeing right?
Thanks guys,
P.S. can I have it tuned with a Rev Limit like 5500?
Oh, also, changed the Synthetic oil at just around 3500 Miles, and it was down 1/4 of a quart... thats about what you guys are seeing right?
Last edited by Danspeed1; Feb 27, 2007 at 07:38 PM.
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Sure, to anything you want. Just keep in mind that the L98 cutoff is FUEL and not spark. Don't let the engine bounce off of it a long time.
Thats not bad at all. Hell the LS6 guys would be jealous! 
Oh, also, changed the Synthetic oil at just around 3500 Miles, and it was down 1/4 of a quart... thats about what you guys are seeing right?
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
the bottom end will limit you to maybe low to mid 6k RPMs.
It's sort of a 'one shot' deal. IOW, it only does it's thing 'once'.
THen you buy a new engine.
But it can be considered to be a VERY good and reliable limiter.
Soooooo.....
I wouldn't rely on it very much if I were.... any of you.
Racer
Joined: Dec 2006
Posts: 325
Likes: 2
From: Chattanooga TN
The ecm's fuel cut rev limit is set to 10,031 rpm for L98s. Fuel resume is set to 9544 rpm.
With these settings the rev limit function has been effectively disabled from the factory.
For shift points: I would suggest as a starting point something like 4800 rpm 1-2, 4600 rpm 2-3 and 4400 rpm 3-4.
With these settings the rev limit function has been effectively disabled from the factory.
For shift points: I would suggest as a starting point something like 4800 rpm 1-2, 4600 rpm 2-3 and 4400 rpm 3-4.
the owners manual does state there is a fuel cut at 5600 rpm,
but i have revved my stock chipped 86 to 6400 rpm
many times, (heads/cam/miniram equipped)
so tequilaboy is correct... no practical fuel cut limit is set.
Racer
Joined: Dec 2006
Posts: 325
Likes: 2
From: Chattanooga TN
it was... for a while....
with 100,000 miles, a rod bearing finally gave up. drove it home from the track with a rod knocking...
rebuilt the shortblock with a reground original crank, and reconditioned orig. rods, fitted with KB 120 pistons.
if i had pulled the pan, and replaced just the rod beaings before i started spinning it so hard, it would probably have been ok for a long time...
with 100,000 miles, a rod bearing finally gave up. drove it home from the track with a rod knocking...rebuilt the shortblock with a reground original crank, and reconditioned orig. rods, fitted with KB 120 pistons.
if i had pulled the pan, and replaced just the rod beaings before i started spinning it so hard, it would probably have been ok for a long time...
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
If the factory manual says that, its dead wrong. It'll take bursts to 6400 just fine. I wouldn't hold it there for circle track racing thoug.
